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Vries, Hugo de, 1848-1935

"Species and Varieties, Their Origin by Mutation"

They are pollinated by bumble-bees, and in some
instances by flies of the genus _Rhingia_, which search for the honey,
brush the pollen out of the anthers and afterwards deposit it on the
stigma. According to systematic views of the monocotyledons the original
prototype of the genus _Iris_ must have had a whorl of six equal, or
nearly equal perianth-segments and six stamens, such as are now seen in
the more primitive types of the family of the lilies, as for instance in
the lilies themselves, the tulips, hyacinths and others. As to the
perianth this view is supported by the existence of one species, the
_Iris falcifolia_, the perianth of which consists of six equal parts.
But species with six stamens are wholly lacking. Heinricher however, in
cultivating some anomalous forms of _Iris pallida_, succeeded in filling
out this gap and in producing [174] flowers with a uniform perianth and
six stamens, recalling thereby the supposed ancestral type. The way in
which he got these was as follows: he started from some slight
deviations observed in the flowers of the pale species, sowed the seeds
in large numbers and selected from the seedlings only those which
clearly showed anomalies in the expected atavistic direction. By
repeating this during several generations he at last reached his goal
and was able to give reality to the prototype, which formerly was only a
hypothetical one.


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